MB495C/D - Microbial Diversity - Fall 1995

MIDTERM EXAM #2

1. What are the three main evolutionary groups ('Kingdoms') of living things? (5 points)

2. How is the cell envelope of Sporomusa (and its relatives) different from those of the other Gram-positive phylogenetic group of Bacteria? (5 points)

3. Describe how stalk structure differs in planctomycetes and prosthecate alpha-purple Bacteria. (10 points)

4. Give an example of an electron donor and an electron acceptor that can be used to run the electron transport chain for the generation of ATP. (10 points)

5. Many Bacteria are photosynthetic and also fix nitrogen. Why does this present a problem for the cyanobacteria, and how have they filamentous cyanobacteria solved this problem? (10 points)

6. Name the 12 main evolutionary branches of Bacteria: (10 points)

    Gram-positive Bacteria          ___________________________
    Chlamydia                       ___________________________
    ___________________________     ___________________________
    ___________________________     ___________________________
    ___________________________     ___________________________
    ___________________________     ___________________________

7. Why is it believed that Bacteria evolved from thermophilic ancestry? (10 points)

8. An outgroup is always required to root a phylogenetic tree; how then was it possible to root the 'Universal' tree (i.e. one that contains all kinds of organisms)? (10 points)

9. Give an example of a bacterial:bacterial symbiosis. How do each of the two organisms benefit from the partnership? (10 points)

10. Describe (diagrammatically, if you wish) one bacterial life/developmental cycle (10 points).

11. How does photosynthesis differ in cyanobacteria and other photosynthetic Bacteria? (10 points)